For the identification of insects and other fauna and flora of South Africa.

Saturday, November 30, 2013

Duiker Berry (Sapium integerrimum)

Family Euphorbiaceae
This is a small tree growing to about 7m in height and found along the eastern coast of SA.

  The fruit has been used in tanning and the earlier settlers made ink from it.
 An infusion from the roots is used to relieve toothache.
  It is a hard wood and wonderful furniture has been made from it.

Thursday, November 28, 2013

River Cabbage (Platycarpha carlinoides)

Family Asteraceae
A very unusual, small plant which grows low on the ground and is a relatively unknown genus of three species endemic to southern Africa. The plants are unusual because the inflorescences occur in the crown of the plant, at the bases of the leaves.

Description
The three species of Platycarpha are quite distinct but they are all perennial herbs with compressed stems and no aerial branches. The above-ground parts of the plants die back after the growing season and the size of re-emerging leaves and inflorescences are dependent on the age of the rootstock and the availability of moisture. This can result in extreme variability in the size of the plants, especially in P. carliniodes. This species has a cartwheel-like growth and the diameter of the plant can vary from around 100 mm to 400 mm.

P. glomerata has an erect growth form, up to 0.6 m tall, whereas P. parvifolia is creeping and often not higher than 60 mm. Leaves of all three species have a smooth green upper surface and white, woolly, lower surface. In P. glomerata, leaves have a glossy, deep green upper surface and are thistle-like and deeply toothed with soft spines on the tips. Leaves of P. carlinoides are also deeply toothed but those of P. parvifolia are only slightly toothed and neither of them has spines.

Inflorescence sizes are also variable and the largest are found in P. carlinoides (20-60 mm in diameter), followed by P. glomerata (30-50 mm) and P. parvifolia (15-35 mm). Inflorescences are composed of numerous flower heads with 3-5 light to dark purple 5-lobed tubular florets. Ray florets are absent. Flower colour fades with age to almost white. The pappus consists of 5-10 long narrow scales. Seeds are glabrous, obscurely ribbed, cylindrical or somewhat compressed.
Flowering times are distinctly different in the three species and reflect the rainfall patterns in the distribution areas. Platycarpha glomerata flowers from November to March; P. carlinoides from March to September and P. parvifolia from August to October.
 Derivation of names
Platycarpha is derived from the Greek platys, for broad, and carpa, for fruit, referring to the broad fruit of P. glomerata. The species name, parvifolia, is Latin, meaning with small leaves; referring to the distinctly smaller leaves of this species; glomerata means clustered in rounded heads, referring to the inflorescence; carlinoides is derived from Carlina, an European genus, and oides to indicate the resemblance in growth forms.
 Conservation status
Although there are often very few specimens in herbaria and little is known about the genus, none of the three species are threatened. Where they occur, one often finds large stands of plants that can measure several square metres.

Distribution
The species of Platycarpha are geographically quite isolated.
  • P. carlinoides is the most widespread of the three species and occurs in Namibia, Botswana and Northern Cape between 700 and 1700 m. It prefers seasonally moist depressions and dry river courses.
  • P. glomerata occurs in the eastern part of the country in inland areas of KwaZulu-Natal and the Eastern Cape at elevations below 500 m. It is prevalent in rural areas, in disturbed areas and along dirt roads.
  • P. parvifolia occurs in the northeastern part of the country at altitudes of 1200-1500 m in the North-West Province, Mpumalanga and Free State. It is often found near dams and streams in short grassveld or on vegetated floodplains.
 Ecology
Platycarpha glomerata and P. parvifolia probably do not have special pollinators as a variety of insects such as butterflies, beetles, bees and flies were observed visiting the flowers.

However, in P. carlinoides the pollinators most frequently observed were large black ants with velvet-white abdomens. Seed dispersal is most probably by insects (particularly ants), water and wind.

Economic and cultural value
Platycarpha glomerata is believed to have some magical powers in KwaZulu-Natal. A concoction of the whole plant (called intelezi ) is sprinkled in the yard around a homestead to protect it against lightning strikes during a thunder storm.
 
In the garden
Plants of this genus will probably not make attractive garden subjects but to gardeners interested in curious plants, they may have some attraction. Very little is known about the cultivation although cultivation from seed should be fairly easy in the correct soil medium and moisture regime. In the wild, Platycarpha glomerata grows on poor, stony soils in moist humid areas, often in disturbed situations. P. carlinoides grows in sandy soil with fine silt, often in depressions occasionally filled with water. P. parvifolia grows in turf soil on floodplains in grassland.

Tuesday, November 26, 2013

Common Screwpine (Pandanus utilis)

Family Pandanaceae  
 Despite its name, a tropical tree and not a pine. It is not endemic to South Africa. Pandanus utilis is a palm-like evergreen tree, ranging in height up to 20 metres (66 ft). They are found in tropical areas and have an upright trunk that is smooth with many horizontal spreading branches with annular leaf scars. Old leaf scars spiral around the branches and trunk, like a screw.
 As with other member of the genus Pandanus, P. utilis lacks secondary growth. The secondary growth of most trees is the production of wood to aid in support of the trunk. Without this supportive structure, the P. utilis grows many pale brown prop roots at the base of the trunk. These adventitious roots arise from the stem above the soil level and help support the plant. These roots not only anchor the tree but also keep it upright during times of heavy winds and rain in tropical regions. Prop roots can be 2.5 to 7.5 centimetres (0.98 to 3.0 in) in diameter.
 P. utilis is dioecious, with the female and male reproducing structures occurring on different plants. Individual plants are either male producing microspores or female producing megaspores. This plant being unisexual allows it to cross-fertilize with other screwpines. The male plants produce fragrant colorful flowers in long spikes. These long spikes are with 8–12 stamens inserted pseudo-umbellately on slender columns 10 to 15 millimetres (0.39 to 0.59 in) long. The female plants produce fruits resembling pineapples or oversized pine cones changing from green to yellow/orange when ripe. The female structure has a 3–8 celled ovary crowned by a sessile stigma.
 P. utilis grows well near the sea, being salt-tolerant. It is a strictly tropical tree that will not survive frost. It grows in full sun to partial shade. Seeds take two to three months to germinate.
 The screw pine has been shown to have many uses. In coastal areas, it has been used for erosion control due to its numerous aerial roots. These roots help bind the sand dunes along the coast from eroding water and wind. The leaves of P. utilis are used in different cultures for thatching and the production of numerous materials. In areas like Madagascar, RĂ©union and Mauritius, the leaves are used to make ropes, baskets, mats, hats, place mats, nets, thatched roofs for homes and even paper. The waxy covering over the leaves makes them especially attractive for baskets and roofs with their natural water-resistant surface. The fruits form a starchy food and can be eaten after cooked.
Info: http://en.wikipedia.org/wiki/Pandanus_utilis

Sunday, November 24, 2013

Cactus (Euphorbia ferox)

Family Euphorbiaceae
 Although different, these are call classified as Euphorbia and not Cactaceae for some reason.
A general test, is whether the plant has milky latex (Euphorbia). This would tell you that it is not a cactus (Cactaceae have clear sap).
 Most of this type of cactus is small, growing only to about 30cm at most.
 They are found in the more arid regions of South Africa.


Friday, November 22, 2013

Karoo Pumpkin (Radyera urens)

Family Malvaceae  
An unusual plant found only in the arid Karoo regions. 
  I was informed not to touch it as the hairs are an irritant to the skin but can find no information on it to confirm this. Apparently no animals eat it either.
 It belongs to the hibiscus family.

The flowers are hidden under the large leaves and I can only presume that because of the heat in this area, it is the only shade around.

Thursday, November 21, 2013

Thistle Violet (Acanthopsis disperma)

Family Acanthaceae
 A small, hairy plant of about 10cm in height.
 Found growing in the Uppington region of the Karoo

Wednesday, November 20, 2013

Matchstick Plant (Aechmea gamosepala)

Family Bromeliaceae 
 An interesting name for this plant.
 Found growing in a garden in St. Lucia so am not sure if this is where they are usually found.



Tuesday, November 19, 2013

Cockscomb Gazania (Gazania pectinata)

Family Asteraceae  
 Flowers about 2.5cm in diameter and grow close to the ground.
 Found in the Nama Karoo region. No information available on them.

Monday, November 18, 2013

Creeping buttons (Pepperomia rotundifolia)

Family Piperaceae  
 An extremely small plant growing on tree trunks in the Woody Cape area between Port Elizabeth and East London.
 The leaves are about 4mm in diameter.


Sunday, November 17, 2013

Fence Aloe (Aloe tenuior)

Family Asphodelaceae
 Plants are small to medium-sized, sprawling shrublets up to 3 m tall, with leaves tufted at the ends of branches. The leaf margins have small teeth. Flowers are borne in slender, nodding racemes and may be red or yellow. Flowering occurs throughout the year, peaking from early to late winter (May to August in South Africa).
 The flowers are visited by bees for their pollen and nectar. There are probably a variety of pollinators.
 The leaves are used traditionally as a purgative and tapeworm remedy, while a bath taken in the foam of the leaves is believed to be a powerful charm to ensure good luck.

Saturday, November 16, 2013

Cobra Lily (Chasmanthe aethiopica)

Family Iridaceae  
 
Chasmanthe aethiopica grows in coastal bush and along the edges of forest patches, mainly in clay soils, from Darling just north of Cape Town, along the coast as far east as Kentani in the Eastern Cape. Its coastal habit means that it rarely experiences extreme climatic conditions in nature and will not withstand temperatures much below freezing.
 
Derivation of name and historical aspects
The species was described in 1759 but for more than 50 years its identity was confused with that of the larger Chasmanthe floribunda. It was only in 1812 that the two species were teased apart. Apart from these two species, the genus Chasmanthe contains just another one, C. bicolor, a rare species that although long known in cultivation, has only recently been relocated in the wild. All three species are well worth cultivating. Chasmanthe floribunda has a yellow form. which does particularly well at Kirstenbosch.
 
Ecology
The long-tubed, orange flowers of C. aethiopica, like those of all three species in the genus, are adapted to pollination by sunbirds. The Lesser Double-collared Sunbird, which frequents coastal scrub, is the most frequent visitor. The flowers secrete large quantitites of nectar that is eagerly sought after by these birds. The fruits develop into large, swollen capsules that split open at maturity to expose the seeds, which are pea-sized and bright orange, and contrast well against the brilliant maroon inner surface of the fruit. The seeds have a thin, fleshy seed coat that is watery and sweet, and are adapted to dispersal by fruit-eating birds, especially Red-winged Starlings. These active birds are attracted to the brightly coloured seeds and fruits and successfully transport the seeds from bush clump to bush clump.
 
Uses and cultural aspects
Few Iridaceae are used in traditional medicine or as food and Chasmanthe aethiopica is no exception. For gardeners, however, its early flowering and ease of cultivation make it a very worthwhile plant.